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Infra-low-frequency neurofeedback alters EEG network efficiency: exploratory evidence from healthy volunteers.

Nuno M P de Matos·Philipp Stämpfli·Erich Seifritz·Mike Brügger
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Abstract

Infra-Low-Frequency Neurofeedback (ILF-NFB) combines classic frequency-band (FB) and infra-low-frequency (ILF) EEG components in implicit training protocols and is increasingly applied in clinical contexts. Yet, the neurophysiological mechanisms underlying ILF-NFB remain to be further elucidated. In this randomized, sham-controlled and double-blind study, we explored the online impact of a one-session ILF-NFB application on EEG correlates in healthy participants (39 analyzed datasets). Continuous 31-channel EEG was recorded during verum and sham feedback in a double-blind, randomized crossover design. In this exploratory analysis approach, functional connectivity was estimated using the debiased weighted phase-lag index (dwPLI) and analyzed with graph-theoretical measures. The results revealed higher global efficiency during verum compared to sham in the Beta1 band (12-15 Hz), reaching significance in the primary comparison but not surviving Bonferroni correction across the five tested bands; block-wise follow-ups showed a significant verum-sham difference in the first half of the neurofeedback session and a directionally consistent pattern in the second half. The Condition × Block interaction was not significant. No consistent differences were observed in other frequency bands, nor for betweenness centrality. While preliminary, these exploratory results point to possible network-level effects during ILF-NFB and motivate further confirmatory work in extended training protocols and clinical populations.

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HumansNeurofeedbackElectroencephalographyAdultMaleFemaleDouble-Blind MethodYoung AdultCross-Over StudiesBrainNerve NetHealthy VolunteersDebiased weighted phase-lag indexEEG functional connectivityGlobal efficiencyGraph theoryInfra-low-frequency neurofeedbackSham-controlled crossoverJournal ArticleRandomized Controlled Trial

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Nuno M P de Matos, Philipp Stämpfli, Erich Seifritz, Mike Brügger. 2026-07-30. Infra-low-frequency neurofeedback alters EEG network efficiency: exploratory evidence from healthy volunteers.. https://doi.org/10.1016/j.neuroimage.2026.122155

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Journal Article; Randomized Controlled Trial resourceAdult subjectBrain subjectCross-Over Studies subjectDouble-Blind Method subjectElectroencephalography subjectFemale subjectHealthy Volunteers subjectHumans subjectJournal Article subjectMale subjectNerve Net subjectRandomized controlled trials study

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